Simplify the following expression: $2\sqrt{125}$.
Explanation: First, try to factor a perfect square out of the radical. $= 2\sqrt{125}$ $= 2\sqrt{25 \cdot 5}$ Separate the radical and simplify. $= 2\sqrt{25} \cdot \sqrt{5}$ $= 2 \cdot 5 \cdot \sqrt{5}$ $= 10\sqrt{5}$